Lighting-fixture.



, 5. a. crm/MHt LIGHT NG FIXTURE.

APPLlcMmN FILED Nov.14.19\3.

Patened May4,1915.

3 SHEETS-SHEET l.

WWA/ES SES f/v VENTO/1? ATTY.

J. R. CRAVATH.

LIGHTING FIXTURE. Y APPLICATION FILED Nov.'14, v1913.

Patented May 4, 1915.

3 SHEETS-SHEET 3.

W/TA/ESSES [NVE/v To@ UNITED STATES PATENT caricia.,

JAMES R. CRAVATH, 0F CHICAGO, ILLINOIS.

Liezn'rma-Frxmtnan.`

Specification of Letters Patent.

Patented May 4, 1915.

Application led November 14, 1913. Serial No. 800,935.

To all 'whom it may coicem.'

Be it known that I, JAMES R. CRAvA'rH,

citizen of the United States, residing at Chicago, in the county of Cook and State of Illlnois, have invented certain new and use- -ful Improvements in Lighting --Fixturesg and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled' in thev art to which it appertains to make and use the same.-

My invention relates to indoor` lighting fixtures and more particularl to fixtures for enabling light to be distributed simultaneously by the so-called direct and.in'di rect lighting methods.

Indirect lighting by the method of directing the rays of a lamp upward against a light colored ceiling is becoming extensively used on account of the pleasant diffused character of the illumination so produced, and because it conceals the source of light from the eye and so prevents the annoyance, discomfort and harmful effects of an ex.- posed light source on the eye. It sometimes happens that for some special purpose it is desirable to have a much higher intensity of illumination in one or moreparts of -a room than is required in other parts. If the lighting is'purely by the indirect method, the light is so diffused to all parts of the room by reflection from a diffuse reflecting ceiling, that it isM not economical by this method to produce'such -localized or specially intense illumination in one part of the room, and it becomes desirable where economy is an object to supplement the general illumination afforded by the" indirect lighting with localized illumination at one or more points. This localized lighting is sometimes best done by the method commonly called direct that is with lamps so placed that the light from the lamp and its reflector equipmentV falls directly on the work without rst being reected from ceiling or walls. If both direct and indirect lighting are provided, it has heretofore Jbeen necessary to use separate fixtures, or at least separate lamps and reflectors on the said fixture, thus making the combination of methods inartistic. The prime objects of my invention are to provldea simple, compact and artisticl fixcumbersome, expensive and oftenv ture which will enable portions of the light froin a given lamp to be distributed respectively by the direct and indirect methods, thereby making it unnecessary to install andv operate separate lamps for each method; to provide means for restricting the light distributed by the direct method to directions not in the normal lines of vision yof occupants of the room lighted by the said lamp; to provide means for adjusting the lamp with respect to the fixture so as to vary the proportions of the light distributed by the direct and indirect methods; and to provide .ready access to the interior surfaces of the fixture for cleaning the same. The means by which I accomplish these objects may be `embodied with substantially equal advantages in a number of different forms, as shown in the accompanying drawings, in which- K Figures l, 5 and 8 are vertical sections of tungsten lamp fixtures embodying my invention. Fig. 2 is a fragmentary elevation of the fixture of Fig. 1 on a reduced scale. Fig. 3 is a fragmentary view of the lower slotted end of the reflector of Fig. 1. Fig. 4- is an enlarged plan view of the bracket supportin the socket in the embodiment of F1g. l. igs. 6 and 7 are fragmentary ver? tical sections through embodiments of my invention equipped respectively with a tungstenlamp and-a mantle gas lamp. Fig. 9 is a fragmentary section through Fig. 8

along the line 9 9. Fig.'10 shows an alternative type of reflector member for use with the construction shown in Fig. 8. Fig. 11 shows a number of lamps and reflector members housed in a single casing.

In Fig. 1, the fixture of my invention consists essentially of an ornamental casing 1.

vSuspended by chains 2 from a canopy 3 seas to produce a comparatively intense direct a. contracted neck portion 8 into two parts each shaped substantially like a truncated conoid, the lower portion 9 thereof closely interfitting the lower end of the casing l while the upper endl() extends approximately to the top of the casing 1. The neck portion of the composite refiector member is positioned close to the portion of the lampl housing the filament or light-emitting partof the lamp, so that the light radiated from the lamp will be redirected in substantially opposite directions by the said reflector portions 9 and 10 as shown by the lines 11 and `12 respectively. The rays of light 12 thus refiected'against the ceiling or diffusing surface 4, together with rays 13 reaching the diffusing medium direct from the filament of the lamp will be reflected and diffused by the diffusing surface, thereby utilizing these upward rays by the so-called indirect method. However7 the rays of light reaching the lower portion 9 of the reflector will be redirected in Ysubstantially downward directions and with the lower portion of the reflector'shaped asin Figs. 1, 5,7, 8 or 10, these downward rays will be concentrated so lighting. It will be evident from Fig. 1 that the proportion of the light flux of the lamp thus reflected respectively in upward and downward directions would depend upon the position of the 'neck 8 or juncture between. .the two refiector portions. vwith respect'to the light-giving portionof the lamp. Thus, if the lamp is raised as shown by the dotted lines, the proportion of light directed downward will be decreased, while the light radiatedupward and' distributedy by means of the reflector portion 10 and the diffusing surface 4 .willbe increased. Consequently, the relative proportions of direct and indirect light can readily be varied to suit different requirements, so as to adapt the same lighting fixture for effecting the lighting of a room which may `be used fora variety' of.

purposes. I am thus able to produce the general illumination of a room by the pleasant method of indirect lighting, while at the same time providing a concentratedlight of adjustable intensity underneathl the fixture so as to suit special requirements for .an abnormally strong illumination for sewing, reading or' other purposes. My investiga.-l tions have shown that, forreading urposes most persons are satisfied with ani lumination intensity lof 1.5l to 2.5 foot candles, and

many even-less. However, some individuals (particularly those over forty-five years -of age or whoseeyesi ht is abnormal) .require as much as five or 4six footcadles, anda like intensity is required by most people forsewing on dark goods if the work is to be donel without straining their eyes. By positioning- .the lamp properly within the fixture, an inf.,

tense illumination is supplied right under the fixture witlibut""making the general illumination of the room unnecearilyl great for the other purposes for which the room is used.`

The adjustable supporting of the lamp 'may bafccomplished in many1 ways. Thus,

Figl shows the lamp 5 as mountediin a socket 14 equipped at its lowe end with afstem -15 clamped .between curved jaws 16 carried by. an arm- -17, which arm is supported by a bracket 18 secured to the casing 1. fyflooseningthe screw 19 whichdraws the curvedjaws 16 toward eachother, the steml may be slid up or down with reference to the said supnorting'arm 'so as to raise or lower the' lamp with respect to the casing and the reflector parts housed therein. To provide for the brackets 18, I equip the lowerend of the reflector 9 with a slot 20,

thereby permitting ythe reflector member of the fixture to be' inserted inthe casing or removed therefromk without disconnecting the bracket ISandthearm supported thereby4 from the casing.. Topennitaccess to the upper surface of the bottom plate .7 for re- 4moving or cleaning thelatter, Ipreferably mount the arm17 upon a pivot 21 carried by the bracket 18, so that the said bracket together with the socket carried thereby may be swung out of its normal position aS shown in dotted linesn Fig. 1. While the various dimensions of the reflector members of. my fixture may be varied greatly whileA producing the combined direct and. indirect lighting effect above described, I preferably proportion the lower Vportion of the reflector member so that it will intercept all rays of light emanating directly in downward directions-at angles lof greater than about 25 lwith the vertical,'. e., the axis -36 of the reflector member.- In other words, I so shape and proportion this reflector part that the angle 30 in Fig. 8 will not be greater than about 25. As the eyebrows of. the average person -will shade the eyes from light coming at lsuch angles when the head is erect, it 'is evident thatwith the head in an normalposition, no direct light from the ament willshine inthe eyes of persons occupyingra room lighted fromsuch a fixture'. liowever, I do -not wish to limit myself to the exact' shape or proportioning of the refiect'oror other parts shown, as there arecases where-it mi htbe desirable to extend1 the angle gf direct illumination, a1- thoug-h it islm'yintention in all cases to keep the light source socompletely shadedl from the eye as toavoidall. annoying vand injurious effects. l El o While I havedescribed the appliance of my invention asequipped with a refiector member having upper and lower portions integrally connected, as .having the lamp supported. by thev casing, andas lutilizing the.

ceiling of the room as a diffusing surface,

' being evident that these may be varied in yio vmany waysl without departing from the' spirit of my invention. Thus, Fig. shows an embodiment in which the fixture is supported from the ceiling 4 by a tubular stem 22 carrying a metal disk 28 which serves as the diffusing surface of the appliance, the casing 1 of the xture being connected to the stem 22 by arms 24. Mounted upon and projecting inwardly of the casing 1 are projections 25 and 26 supporting the upper and lower portions and 9 of the reflector respectively, these reliector portions being separated by an annular space permitting the small portion of light' to e'nter the space between the said reflectors and the casing 1 so as to li ht the glass beads or translucent portions 2 mounted in perforations in the casing 1. In this case, the position of the cent ends,

lamp with respect to the reiector members may be made adjustable by vertically moving the sleeve 28 to which arms 24 are attached, said sleeve telescopically intertting the tubular stem 22 and being clamped thereon by a screw 29.

The casing 1 may be ornamental as desired, and if the reflector members are entirely opaque and contiguous at their adjaas in Fig. 1, the casing may be made of any opaque material such as metal, wood, paper, fiber or lplaster which can be worked into the desired ornamental design. However, a portion of the light of the lamp may also be used to illuminate parts of the casing, thereby adding` to the ornamental effect of the latter, by providing openings in the reflector member or by maklng the latter of a translucent material. For example, Figs. 8 and 9 show a reector member 32 of dense opalor other translucent material housed within an inclosure consisting of a lanternframe 33 supporting glass panels 34. Likewise, Fig. 10 shows a section of a similar ixture equipped with an opaque reflector member having perforations 35 through which light may pass from the lamp to the panels 34 of the inclosure.

Instead of extending the lower end of the reflector 9 substantially to the lower end of the casing, the interior of the lower 'end of the casing 1 may be equipped with a reiecting surface, thereby enabling the rellector 9 to be shortenedsas in Fig. 5. Or, if desired, the entire interior surface of the casing may be equipped with a. reliecting surface, as in Fig. 6, thereby enabling me to dispense with the separate reflector portion 9.v So also, if the appliance of my invention is to be used in shops or other places where the cost of an ornamental casing would not be warranted, the latter may be omitted altogether as in Fig. 7. In any case, it will be evident that by thus utilizing the light of a single lamp in twogsubstantially opposite directions, I am enabled to make efficient fixtures much shorter than corresponding fixtures employing two lamps one placed above lthe other. I have thus beenl enabled to make fixtures which can be used in rooms having ceilings as low as 8.5 to 9.5 feet from the floor, in which rooms two-lamp fixtures would not be practical on account of insuiicient head room. Moreover, I am thus able to combine an indirect lighting effect with a.. certainamount of direct but well shadedlighting `(and, in the case of ixtures having translucent caslngs, with the soft illumination of an ornamental housing) by the use of a single lamp and socket. This reduces both the first cost and the cost of maintenance over that which would be required with fixtures equipped with separate lamps for the direct and indirect portions of the lighting. However, I do not wish to be limited to fixtures equipped with only one lamp, as a number of lamps and reiiector members might be housed in a single casing, as shown sectionally in Fig. 11.

I claim as my invention:

1. A lighting fixture comprising a frame, a casing and a tubular reflector member both supported thereby, the reflector member housed by Athe casing and equipped intermediate of its ends with a contraction dividing the same into two substantially truncated conoidal i'eiiectors opening in. opposite directions; a socket adjustably supported by the casing, and a lampl mounted in the socket, the adjustable -supporting of the socket permitting the lamp to be moved with respect to the said contraction of vthe rey Hector member. v

2. A lighting fixture comprising an axially vertically' disposed tubular reflector lrefiector member, and a lamp supported by member equipped intermediate its ends with A the casing member and so disposed with respect to the reflector member and casing that the lower edges of one ofthe latter will intercept all direct rays of light emanating from the lamp atangles'of more than about twenty-five degrees with thev axis of the reflector member.r

' 3. A lighting fixture' including an at least partially translucent casing member, an at least partially translucent tubular reflector divided by a contraction into two reflectors flaring in opposite directions, a lamp mounted' within the reflector memberand means associated with said lamp for varying the position of the latter with respect to said contractiom'thereby simultaneously varymg ymember housed and supported thereby and the proportion of the light distributed by the respective-reflectors and the casing member.

4. In a lighting fixture, the combination p with a lamp and a socket therefor, a pair o f reflectors jointly housing the said lamp and reflecting portions of the light `therefrom in substantially opposite directions, a casing housing the said reflectors, an arm connecting the socket and the casing to support the former, and a translucent cover for one end of the casing, the said armbeing movable to move the socket out of its uormal position to permit access to said cover through the other end of the casing.

5. In a lighting fixture, the combination with a lamp and a socket therefor, a pair of reflectors jointly housing the said lamp and reflecting'portions of the light therefrom in substantially opposite directions, a

casing housing the said reflectors, and a detachable translucent cover for one end lof the casing.

6. A lighting fixture comprising a pair of reflector elements having a common vertical axis and flaring in opposite directions, av translucent casing housingat least one of said reflector elements, a lamp housed jointly by the reflector elements, and means associated with at least one of said reflector elements for permitting a portion of the light of the lamp to light the interior of said translucent casing. j y

`7. Ina lighting fixture, the combination with a lamp and a tubular casing housing the lamp, of a translucent bottom for said casing, and a tubular reflector member interposed between said lamp and easing and vcarried bythe said bottom, said member comprising a pair of axially alined reflectors 40 flarin inopposite directions.

8. li a lighting fixture, the combination with a lamp, of a pair of reflectors jointly housing the lamp' and reflecting portions of the light thereof respectively in upward and downward directions; a support for said lamp, means for adjusting the lamp with respect to said support to vary the relative proportion of the light reflected in the said directions; and means associated with said 5t lamp and support for limiting the relative adjustment thereof in one direction, said last-named means so disposed as .to coact with the end of one of said reflectors to limit the direct downward rays of light of 5:3

the lamp to angles of not exceeding about thirty4 degrees with the vertical axis of the said reflectors. i

9. A lighting fixture comprising a pair of reflector elements haring a common vertical ,axis and flaring in opposite. directions, a

JAMES R. CRAVATH.

Witnesses:

ALBERT SCHEIBLE, .M. M. Bom. 

